geological or fossil?

[abyssunder]

It will be interesting to know if the pellets have crescentic internal canals, or not.

[Rowboater]

4 hours ago, GeschWhat said:

If you come across these often, I wouldn't mind having a peak at a few under the microscope as well. 

For sure I can send the beach ones.  If you wait, I might can find some less weathered in my stuff.  Just send a shipping address through thefossilforum e-mail.

[GeschWhat]

1 hour ago, Rowboater said:

For sure I can send the beach ones.  If you wait, I might can find some less weathered in my stuff.  Just send a shipping address through thefossilforum e-mail.

I'm in no rush and can wait for less weathered stuff. I will send you a PM with my address. 

[Rowboater]

Sent GeschWhat a few as well.  Will be interesting to hear their conclusions!

[ynot]

On 6/16/2018 at 8:34 AM, Rowboater said:

Have sent samples to ynot, hopefully he can figure out what they are. 

I got the pieces today and looked at them under magnification.

I stick with My original assessment of staurolite crystals. They are very worn which makes it hard to see the crystal shape, but it is there.

Staurolite is a crystal that forms in metamorphic  mica schists under high pressure and heat.

There are several known staurolite locations in Virginia.

They are often called "fairy cross" crystals, because of their habit of twinning.

[DPS Ammonite]

1 minute ago, ynot said:

I got the pieces today and looked at them under magnification.

I stick with My original assessment of staurolite crystals. They are very worn which makes it hard to see the crystal shape, but it is there.

Staurolite is a crystal that forms in metamorphic  mica schists under high pressure and heat.

There are several known staurolite locations in Virginia.

They are often called "fairy cross" crystals.

What do you see in the matrix? Is it mica or other metamorphic mineral? 

[ynot]

Just now, DPS Ammonite said:

What do you see in the matrix? Is it mica or other metamorphic mineral? 

Most of the mica has weathered off, leaving trace amounts between the crystal and the pieces are jumbled staurolite. I see nothing else in the rock.

I found many simulare pieces in the Taos NM area while hunting staurolite crystals there.

[Rowboater]

Thanks ynot!  My last two trips I went looking expressly for these "rod filled rocks" but found none.  We of course have Fairy Stone State Park, 4 1/2 hours away, and the "fairy stones" I've seen dwarf these!  

 

I did note more in a few steinkern pieces (on one side), while searching for other stuff:

[ynot]

3 hours ago, Rowboater said:

We of course have Fairy Stone State Park, 4 1/2 hours away, and the "fairy stones" I've seen dwarf these!  

Upriver?

Crystals come in all sizes., with most of any type being on the smaller side. (Most people only keep the larger ones.)

 

Your new pictures do not look the same to Me. (But there is so little in focus it is hard to see the new pieces.)

[Plax]

those rods in the steinkerns don't look like crystals to me. Perhaps we're talking about two different things.

[Rowboater]

Possibly, GeschWhat thought they were multiple different things.  I cannot see that well and to me they were just tiny "rods" concentrating to varying extent in different pieces.

5 hours ago, Rowboater said:

Thanks ynot!  My last two trips I went looking expressly for these "rod filled rocks" but found none.  We of course have Fairy Stone State Park, 4 1/2 hours away, and the "fairy stones" I've seen dwarf these!  

 

I did note more in a few steinkern pieces (on one side), while searching for other stuff:

1 hour ago, ynot said:

Upriver?

Crystals come in all sizes., with most of any type being on the smaller side. (Most people only keep the larger ones.)

 

Your new pictures do not look the same to Me. (But there is so little in focus it is hard to see the new pieces.)

Hi ynot,

Fairy Stone Park is 278 miles SW of here, and the Rappahannock comes from the northwest; don't think they have much to do with each other.  My interest was in what the little rods could be and staurolite crystals seems a good explanation for at least part of what I've found, particularly after comparing to Google images.  Some seem to be mixed in with other stuff, but would not be surprised if weathered crystals in the sand, along with other inclusions, ended in steinkerns or other matrix.  I just used the scanner for the images, could take cell phone photos but again it's not going to show much detail.  Unlike some of the small pieces I sent, the rods/ crystals are not raised on the steinkern piecess; only picked them up because some seemed to have a porcelain-like glaze on them; noticed the patterns of rods much later (most have the "glaze", only a few have the rods). 

 

 

38 minutes ago, Plax said:

those rods in the steinkerns don't look like crystals to me. Perhaps we're talking about two different things.

 

[Plax]

the glaze is the surface of the fine sediment that was filling the shell along with the inclusions. After the shell dissolved away the indurated sediment and inclusions were exposed. We are looking at gastropod steinkerns; no?

[Rowboater]

15 hours ago, Plax said:

the glaze is the surface of the fine sediment that was filling the shell along with the inclusions. After the shell dissolved away the indurated sediment and inclusions were exposed. We are looking at gastropod steinkerns; no?

Gastropods seem likely, but not sure I have a perfect complete one.  The clam ones tend to be complete (but boring, and missing the glaze).  The glaze is striking and for a while I was convinced they must be porcelain shards (some looked like lips of an opening, some like small handles), although I had no idea how they ended up in the bank where I was digging.  Still, it is a creek bed that has been fossil hunted a long time and probably the banks have shifted multiple times with hard rains/ tropical storms.  Fortunately nobody seemed interested in the smaller stuff.

[DPS Ammonite]

@RowboaterWe should be able to differentiate between staurolite crystals and fecal pellets by looking at their physical properties.

 

Let us look at the properties of staurolite.

https://geology.com/minerals/staurolite.shtml

Form: six sided crystals often twinned at 90 &60 degrees.

Vitreous to resinous luster.

7 -7.5 hardness. No streak since harder than plate.

 

Fecal pellets: probably composed of sand, silt, clay or various carbonates all which are softer than 4.5 or are too fine (sand & silt) to get a hardness on.

 

Take a sewing needle to get hardness on rods/pellets/crystals. Are they scratched? Look for crystal faces and twinning on the rods. Any? Consider cracking one of the nodules open to see if you can see any crystal faces. What is the luster on the rods? Try to get a streak by rubbing the rock on an unglazed porcelain tile or the underside of a toilet tank lid. What happens? 

 

Let us us know what you find out.

 

Thanks,

John

 

 

 

 

[Rowboater]

On 6/23/2018 at 2:59 AM, DPS Ammonite said:

@RowboaterWe should be able to differentiate between staurolite crystals and fecal pellets by looking at their physical properties.

 

Let us look at the properties of staurolite.

https://geology.com/minerals/staurolite.shtml

Form: six sided crystals often twinned at 90 &60 degrees.

Vitreous to resinous luster.

7 -7.5 hardness. No streak since harder than plate.

 

Fecal pellets: probably composed of sand, silt, clay or various carbonates all which are softer than 4.5 or are too fine (sand & silt) to get a hardness on.

 

Take a sewing needle to get hardness on rods/pellets/crystals. Are they scratched? Look for crystal faces and twinning on the rods. Any? Consider cracking one of the nodules open to see if you can see any crystal faces. What is the luster on the rods? Try to get a streak by rubbing the rock on an unglazed porcelain tile or the underside of a toilet tank lid. What happens? 

 

Let us us know what you find out.

 

Thanks,

John

 

 

 

 

Here's your test.  took a small piece and an unglazed tile and scraped and saw a streak.  A few rods disappeared, but the piece is heterogeneous, and it still difficult to conclude whether some rods are staurolite, as ynot is convinced from his samples, and other rods are something else, perhaps coprolites.  Some rods were also scratched  or a chunk removed after picking at them with a sewing needle.

 

[sixgill pete]

On 6/9/2018 at 10:27 AM, Rowboater said:

(sorry forgot the scale penny, but about 1 cm X 1 cm X 0.5 cm

Rowboater, it is better to give the size as you did in metric measurements or use a small rule for scale. Using a U.S. penny gives no scale to our international members who may view this post. Many of them have no idea of the size of a penny.

[FranzBernhard]

It is almost impossible to have staurolite crystals and coprolites in the same specimen!

Btw, some of the staurolite crystals could have been superficially or totaly transformed to mica etc., which is usual case, making the rods soft and crumbly.

Franz Bernhard

[DPS Ammonite]

14 hours ago, Rowboater said:

Here's your test.  took a small piece and an unglazed tile and scraped and saw a streak.  A few rods disappeared, but the piece is heterogeneous, and it still difficult to conclude whether some rods are staurolite, as ynot is convinced from his samples, and other rods are something else, perhaps coprolites.  Some rods were also scratched  or a chunk removed after picking at them with a sewing needle.

 

I think that they are not staurolite crystals since they left a streak and are softer that the porcelain streak plate/tile. Staurolite is harder than streak plates and leave no streak. Thanks for doing the tests.

 

Long distance science can be fun and informative especially when you cannot see the rock in person.

[ynot]

 WHOOPS.

I made a mistake. I had not done any tests and made My identification on a visual appearance alone.

@Rowboater's test made Me go back and take a closer look and do some testing.

Streak is black. 

Hardness is 5.5 - 6. (Hrd to scratch with knife, will not scratch knife.)

The matrix(?) is not mica.

 

So it is not staurolite.

[GeschWhat]

Thank you so much for sending me the samples. I can say with confidence that all three samples you sent are clusters of fecal pellets. @Carl can likely provide additional info.

[GeschWhat]

For the first two, I'm thinking Palaxius ichnospecies (10 canals). The third could be the same, but the canals aren't as distinct.

[ynot]

37 minutes ago, GeschWhat said:

. I can say with confidence that all three samples you sent are clusters of fecal pellets.

I will defer to Lori's great knowledge of poops.

After seeing Her post above, I can see the same structures in the pieces I received.

Today I learnt that poops can look like crystals, who'd of thunk that!

 

@Rowboater...

[Carl]

1 hour ago, GeschWhat said:

Thank you so much for sending me the samples. I can say with confidence that all three samples you sent are clusters of fecal pellets. @Carl can likely provide additional info.

Aren't those just perfect callianassid turds?! Wow... I'm thinking Palaxius, too, but I could sure stand to learn a lot more about these guys.

[GeschWhat]

9 minutes ago, Carl said:

Aren't those just perfect callianassid turds?! Wow... I'm thinking Palaxius, too, but I could sure stand to learn a lot more about these guys.

Me too...I'd like to collect all 27 

[GeschWhat]

35 minutes ago, ynot said:

I will defer to Lori's great knowledge of poops.

After seeing Her post above, I can see the same structures in the pieces I received.

Today I learnt that poops can look like crystals, who'd of thunk that!

 

@Rowboater...

Aren't these fun? Carl is the real expert on this type. He taught me everything I know. Poop is so under rated! I want to find some Helicerina isp. Just look at all the fun shapes!!!